测sort与qsort耗时

//测试sort与qsort耗时

#include <stdio.h>  #include <stdlib.h>  #include <time.h> #include <algorithm>using namespace std;int cmp( const void *a , const void *b ){  int *c=(int *)a; //(int*)是强制类型转换  int *d=(int *)b;   return *c-*d;}int a[100000005],b[100000006];int main()  {      int g=1;    srand((int)time(NULL));//产生随机因子for(int i=0; i<100000000; i++){  int j=1+rand()%100000000;//获取随机数   if(g==1)   g=-1;   else g=1;   j=j*g;  a[i]=b[i]=j;}    clock_t start,finish;      double TheTimes;      start=clock();       sort(a,a+100000000);    finish=clock();      TheTimes=(double)(finish-start)/CLOCKS_PER_SEC;    printf("sort耗时 %f秒。\n",TheTimes);         start=clock();       qsort(b,100000000,sizeof(int),cmp);    finish=clock();      TheTimes=(double)(finish-start)/CLOCKS_PER_SEC;    printf("qsort耗时  %f秒。\n",TheTimes);      return 0;  }